Adjusting, cleaning and reparing landis heads
To obtain the best results from the chasers used in a die head, it is necessary that the die head be cleaned and adjusted periodically. The instructions contained herein will aid materially in maintaining the efficiency of the die head and in insuring satisfactory service to the user.
The instruction contained in this article cover the cleaning and repairing of Landis Heat Treated and Hardened and Ground Die Heads.
Lubrication of Heat Treated Heads
The smaller size Landis Heat Treated Heads are lubricated by removing the oil orifice set screw and placing by means of an oil can, high grade lubricating oil into the orifice.
The larger heads are equipped with a special ball oiler. Oiling is accomplished by depressing the ball with the oil can spout and injecting the oil. When the spout is removed the ball moves back into position and prevents the entry of dirt and chips into the orifice.
The 4" and 6" Lango Heads are lubricated through the trunnions by means of flush mounted Alemite fittings. These fittings are srerviced with a standard grease gun fitted with Z-737 or Alemite #1452 nozzles and using machine oil as the lubricant. Grease is not recommended due to the close tolerances of the operating parts.
Lubrication of Hardened And Ground Heads
The various parts of the Lanco VV and VVV, Landmatic H and HH, and Landex LLL Hardened and Ground Heads should be lubricated each time the heads are dismantled for changing chaser holders or cleaning.
For those Hardened and Ground Heads which do not require dismantling to change chaser holders, lubrication is through Alemite fittings. The 1" Lango VV Head and the 2" Landmatic HH Head require lubrication in four locations on the head body by an Alemite Gun with a 1 1⁄4" #41613 gun nozzle. The 1 1⁄2" and 2" Lanco VV Head can be serviced by a standard Alemite gun, through fittings located on the chaser holder slides.
All Landis Die Heads are carefully lubricated upon assembly prior to shipment and a heavy rust-proof grease is applied to protect the head in transit. If this grease is removed by a solvent, another complete lubrication of the head is highly recommended.
A die head used in conjuction with a sulphur base oil coolant receives lubrication from this source and requires lubrication only once every forty hours of operation. In threading operations where a water base coolant or no coolant is used the die head should be lubricati=ed daily. To obtain maximum benefit of the wearing qualities available in Landis Die Heads, they should be dismantled periodically, as conditions dictate, for cleaning, inspection and lubrication.
Oil Specifications: A high grade machine lubricating oil, viscosity 124 - 175 S.S.U at 130F, is recommended.
To Clean The Head
The flow of cutting lubricant or coolant over the die head will tend to wash, fine particles of metal, scale, etc, from the work into the die head, and for this reason the head should be dismantled and thoroughly cleaned at regular intervals. Special attention should be given to the chasers and the chaser holders. The dovetail of the chaser, the chaser seat in the chaser holder and the chaser clamp seat in the chaser holder must be kept clean and free of dirt and cuttings. Otherwise, the alignment of the chasers will be destroyed and this will not only make it impossible to obtain accurate threads, but it will also materially increase wear on the cutting edges of the chasers.
The under surfaces of the chaser holders for Landis Heat Treated Die HEads are machined to insure a good bearing on the face of the die head. Should this surface become bruised, all irregularities on the surface should be removed with a fine-cut file or scraper.
All bearing surfaces of the Landis Hardened and Ground Die Heads are file hard. However, should any of these bearing surfaces become nicked or bruised, the bruises may be removed with a hone, although care should be taken not to destroy the original bearing surfaces.
To Adjust The Trunnions
These instructions apply to the Landis Heat Treated Die Heads only.
The chaser holders of the die heads listed above must not fit tightly against the front face of the head, but must have a certain amount of end play, known as trunnion play. The trunnion play prevents the chaser holders from binding on the head and provides a floating action for the chaser holders which provides perfect chaser tracking. The table of trunnion play on page 164 gives the correct amount of trunnion play for all Landis Die Heads.
Before adjusting the trunnions, remove all bruises from the under surfaces of the chaser holders and from the face of the die head. Then replace the chaser holders on the head.
To adjust the trunnions of a Lango, Landmatic or Landex Heat Treated Head, remove the head from the machine (the shanks of the Landmatic and Landex Head must be removed also), unscrew the trunnion locking screw "A" of each trunnion and back off the trunnion adjusting nut "B". This must be done with the chaser holders in position on the die head.
Insert a thickness gage or feeler, the thickness of which is 003" or 08m/m in excess of the maximum recommended trunnion play, between the under surface of the chaser holder and the face of the closing ring at point "C" below the chaser abutting screw. Thighten the trunnion adjusting nut "B" without forcing and lock it in position with the trunnion locking screw "A". Then place thickness gage of the proper dimension in position and draw up the trunnion adjusting nut "B" and the trunnion locking screw "A" as a unit until the thickness gage fits nearly between the chaser holder and the closing ring. The correct trunnion play will then be established. The trunnion play of the chaser holders must be uniform.
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